Infrared light is that portion of the electromagnetic spectrum adjacent to the long wavelength, or red end of the visible light range. Invisible to the eye, it can be detected as a sensation of warmth on the skin. The infrared range is usually divided into three regions: near infrared (nearest the visible spectrum), with wavelengths 0.78 to 3.0 microns; middle infrared, with wavelengths 3 to 30 microns; and far infrared, with wavelengths 30 to 300 microns. Most of the radiation emitted by a moderately heated surface is infrared light; it forms a continuous spectrum. Molecular excitation also produces copious infrared radiation but in a discreet spectrum of lines or bands.
In application, infrared sensors on the ground, or in aircraft or spacecraft, can detect such hot spots as motor-vehicle engines, hot jet engines, missile exhaust, and even campfires. They generally have good location accuracy and high sensitivity to signals, without registering such false targets as sun reflections. Infrared imaging detectors are also used. In the very near infrared region, specially sensitized photographic film forms camouflaged-revealing images. More important are the detectors used in the far infrared region; objects at room temperature radiate sufficient energy for detection at ranges of several miles. Infrared imagery can have longer range than image intensifiers and can operate without starlight.
While the prior art has shown a vast assortment of devices that can detect infrared radiation, there is little known in the prior art for the conversion of visible light into infrared radiation. Typically, in military exercises, objects must be individually heated in order to produce infrared radiation. Another apparatus used is the Bly Cell. The Bly Cell projects an image onto a polymer sheet at great intensity such that the light itself serves to heat the sheet. An image is produced since the most intense portions of the light will elevate the temperature of the polymer sheet a greater amount than the less intensely illuminated portions of the projected image. The Bly Cell, however, requires a large amount of power for image generation. In addition, the spatial and temporal resolution of the image is poor.
It is an object of the present invention to provide a dynamic infrared simulation cell which is capable of converting a light image into an infrared image.
It is another object of the present invention to provide an infrared simulation cell that operates with low amounts of power and energy consumption.
It is another object of the present invention to provide an infrared simulation cell that offers a high level of spatial and temporal resolution.
It is still another object of the present invention to provide an infrared simulation cell that is capable of operating at realtime speeds for the projection of "moving" infrared pictures.
These and other objects and advantages of the present invention will become apparent from a reading of the attached Specification and appended claims.